crypto: add getIntOption function to reduce dupl

This commit adds a getIntOption function to reduce the code duplicated
for getting the padding, and saltLength options.
PR-URL: #20247
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Tobias Nießen <tniessen@tnie.de>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

Author: danbev

lib/internal/crypto/sig.js

@@ -53,6 +53,25 @@ Sign.prototype.update = function update(data, encoding) {
 returnthis;
 };
 
+functiongetPadding(options){
+returngetIntOption('padding',RSA_PKCS1_PADDING,options);
+}
+
+functiongetSaltLength(options){
+returngetIntOption('saltLength',RSA_PSS_SALTLEN_AUTO,options);
+}
+
+functiongetIntOption(name,defaultValue,options){
+if(options.hasOwnProperty(name)){
+if(options[name]===options[name]>>0){
+returnoptions[name];
+}else{
+thrownewERR_INVALID_OPT_VALUE(name,options[name]);
+}
+}
+returndefaultValue;
+}
+
 Sign.prototype.sign=functionsign(options,encoding){
 if(!options)
 thrownewERR_CRYPTO_SIGN_KEY_REQUIRED();
@@ -61,23 +80,9 @@ Sign.prototype.sign = function sign(options, encoding) {
 varpassphrase=options.passphrase||null;
 
 // Options specific to RSA
-varrsaPadding=RSA_PKCS1_PADDING;
-if(options.hasOwnProperty('padding')){
-if(options.padding===options.padding>>0){
-rsaPadding=options.padding;
-}else{
-thrownewERR_INVALID_OPT_VALUE('padding',options.padding);
-}
-}
+varrsaPadding=getPadding(options);
 
-varpssSaltLength=RSA_PSS_SALTLEN_AUTO;
-if(options.hasOwnProperty('saltLength')){
-if(options.saltLength===options.saltLength>>0){
-pssSaltLength=options.saltLength;
-}else{
-thrownewERR_INVALID_OPT_VALUE('saltLength',options.saltLength);
-}
-}
+varpssSaltLength=getSaltLength(options);
 
 key=toBuf(key);
 if(!isArrayBufferView(key)){
@@ -119,23 +124,9 @@ Verify.prototype.verify = function verify(options, signature, sigEncoding) {
 sigEncoding=sigEncoding||getDefaultEncoding();
 
 // Options specific to RSA
-varrsaPadding=RSA_PKCS1_PADDING;
-if(options.hasOwnProperty('padding')){
-if(options.padding===options.padding>>0){
-rsaPadding=options.padding;
-}else{
-thrownewERR_INVALID_OPT_VALUE('padding',options.padding);
-}
-}
+varrsaPadding=getPadding(options);
 
-varpssSaltLength=RSA_PSS_SALTLEN_AUTO;
-if(options.hasOwnProperty('saltLength')){
-if(options.saltLength===options.saltLength>>0){
-pssSaltLength=options.saltLength;
-}else{
-thrownewERR_INVALID_OPT_VALUE('saltLength',options.saltLength);
-}
-}
+varpssSaltLength=getSaltLength(options);
 
 key=toBuf(key);
 if(!isArrayBufferView(key)){